目的 探讨高压氧预处理对移植术后随意皮瓣组织中氧自由基的影响及其与皮瓣存活的关系.方法 于每只SD大鼠背部构建一个10.0 cm×2.5 cm的超长随意皮瓣移植模型.将45只SD大鼠随机分为3组.高压氧预处理组(n=15):大鼠皮瓣移植术前,给予高压氧处理4次(2次/d,连续2d);术后高压氧组(n=15):大鼠皮瓣移植术后,给予高压氧处理4次(2次/d,连续2d);对照组(n=15):大鼠皮瓣移植术前及术后,均处于常压空气中.术后即刻和术后第2、4、6天,在距皮瓣蒂部4.0cm处进行组织取材,分别采用免疫组织化学法、总超氧化物歧化酶测定试剂盒、丙二醛测试盒,检测皮瓣组织中超氧化物歧化酶(SOD)及丙二醛(MDA)含量的变化水平,并进行术后第2、4、6天皮瓣的组织病理学观察.结果 术后即刻,SOD含量在高压氧预处理组中显著高于术后高压氧组和对照组(P<0.01),且MDA含量显著低于其余两组(P<0.01),而术后高压氧组的SOD和MDA含量与对照组相比差异无统计学意义(P>0.05);术后第2天,高压氧预处理组的SOD含量仍显著高于术后高压氧组和对照组(P<0.01),且MDA含量亦显著低于其余两组(P<0.01);术后第4天,SOD含量在高压氧预处理组和术后高压氧组中差异无统计学意义(P>0.05),但两者均显著高于对照组(P<0.01),而高压氧预处理组中的MDA含量则低于术后高压氧组(P<0.05),且两者均显著低于对照组(P<0.01);术后第6天,SOD含量变化趋势同第4天,而MDA含量在高压氧预处理组和术后高压氧组中差异无统计学意义(P>0.05),且两者均显著低于对照组(P<0.01).术后第6天,高压氧预处理组中的大鼠移植皮瓣存活率均高于其余两组(P<0.05).结论 高压氧预处理可明显提高移植术后随意皮瓣组织中的SOD含量,并能明显降低皮瓣组织中的MDA水平,进而通过影响氧自由基平衡促进移植术后的皮瓣存活.
Objective To explore the effect of hyperbaric oxygen preconditioning on oxygen-free radicals in random-pattern flaps after transplantation and its relationship to flap survival.Methods A total of 45 SD rats were randomly divided into three groups.An overlength random-pattern flap with a size of 10.0 cm × 2.5 cm was constructed on the back of each SD rat.In the hyperbaric oxygen preconditioning group (n=15),hyperbaric oxygen was given to rats 4 times (2 times a day,for 2 consecutive days) before transplantation.The postoperative hyperbaric oxygen group (n=15) received hyperbaric oxygen 4 times (2 times a day,for 2 consecutive days) after flap transplantation.Rats in the control group (n=15) were in constant pressure atmospheric air both before and after flap transplantation.Tissue samples were taken at 4.0 cm to the pedicle of the flap immediately (day 0) and at days 2,4 and 6 after operation.The contents of superoxide dismutase (SOD) and malondialdehyde (MDA) in the flap were detected by the immunohistochemical method,total SOD assay kit,and MDA test kit.Histopathological observation of the flaps was performed at days 2,4,and 6 after operation.Results Immediately after operation (day 0),the content of SOD in the hyperbaric oxygen preconditioning group was significantly higher than that in the postoperative hyperbaric oxygen group (P<0.01),and the content of MDA was significantly lower than that of the other two groups (P<0.01).Between the postoperative hyperbaric oxygen group and the control group,the difference in SOD and MDA content was not statistically significant (P>0.05).On the second day after operation,the content of SOD in the hyperbaric oxygen preconditioning group was significantly higher than that in the postoperative hyperbaric oxygen group and the control group (P<0.01),and MDA content was significantly lower than that of the other two groups (P<0.01).On the 4th day postoperative,the SOD content in both the hyperbaric oxygen preconditioning group and the postoperative hyperbaric oxygen group was significantly higher than that in the control group (P<0.01).However,the difference between the hyperbaric oxygen preconditioning group and the postoperative hyperbaric oxygen group was not statistically significant (P>0.05).The MDA content of the hyperbaric oxygen preconditioning group was lower than that of the postoperative hyperbaric oxygen group (P<0.05),and both groups were significantly lower than that of the control group (P<0.01).On the 6th day after operation,the change trend of SOD content was the same as the 4th day.There was no statistical difference in the MDA content between the hyperbaric oxygen preconditioning group and the postoperative hyperbaric oxygen group (P>0.05),and both of them were significantly lower than that of the control group (P<0.01).On the 6th day after operation,the survival rate of the transplanted flap in the hyperbaric oxygen preconditioning group was higher than that in the other two groups (P <0.05).Conclusion Hyperbaric oxygen preconditioning can significantly increase the SOD content and can reduce the MDA level in random-pattern flaps after transplantation,and promote the flap survival after transplantation by affecting the balance of oxygen free radicals.